高碳冷拔钢丝退火过程中的显微组织演变及其对强度的影响  

Microstructure evolution of high carbon cold drawn steel wire during annealing and its effect on strength

作　　者：刘瑞娟[1] LIU Ruijuan(Hebi Polytechnic,Hebi 458030,China)

机构地区：[1]鹤壁职业技术学院,河南鹤壁458030

出　　处：《材料研究与应用》2020年第3期184-189,共6页Materials Research and Application

摘　　要：利用常规力学性能检验设备、透射电镜及差示扫描量热仪,研究了一种冷拔高碳钢线材在退火过程中的强度变化及其对应的组织演变.试验结果表明:冷拔钢丝在加热过程中的组织共发生三阶段变化,第一阶段和第二阶段的性能变化主要是由于碳原子扩散至片状铁素体中的位错附近和片状渗碳体的部分退化分解,该两阶段不会导致冷拔钢丝强度的大幅度恶化,与低温退火(200℃)阶段一致;第三阶段是由于片状渗碳体的大幅度球化或细小渗碳体颗粒的重新析出,该组织变化伴随着强度的剧烈恶化,与高温退火(400℃以上)阶段一致,在实际热镀过程中应尽量避免.The strength and microstructure evolution of a cold-drawn high carbon steel wire during annealing were studied by means of conventional mechanical properties testing equipment,transmission electron microscope and differential scanning calorimeter.The results show that three stages of microstructure change of cold drawn steel wires occurred in the heating process.The performance changes in the first and second stages are mainly due to the diffusion of carbon atoms near dislocations in the flake ferrite and the partial degradation and decomposition of the flake cementite.These two stages do not lead to a significant deterioration of the strength of cold-drawn steel wire,which is consistent with the low-temperature annealing(200℃)stage.The third peak is due to the large spheroidization of flake cementite or the re-precipitation of fine cementite particles.The change of microstructure is accompanied by the severe deterioration of strength,which is consistent with the high-temperature annealing(above 400℃)stage and should be avoided as much as possible in the actual hot-dipping process.

关 键 词：冷拔钢丝 渗强化机理、渗碳体 DSC曲线 

分 类 号：TG142.1[一般工业技术—材料科学与工程]